How do you model cases where the reservation fails, where the inventory operation is already complete, etc? Basically conditional transitions based on some data received? Also, where does the actual I/O happen? Presumably there is some shell that drives the state machine that does the I/O before or after executing the transition?
I think this makes sense. I’m eager to try it. Some residual questions: what is “untyped” in this case and what is “PostConditional” (an enum of possible states?)? How do subsequent transitions work?
I also just realized that delegating to “UntypedStateMachine” for I/O probably doesn’t allow for Sans-I/O, right? Presumably the UntypedStateMachine must commit to either being sync or async and that must propagate to the typestate state machine itself, no?
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How do you model cases where the reservation fails, where the inventory operation is already complete, etc? Basically conditional transitions based on some data received? Also, where does the actual I/O happen? Presumably there is some shell that drives the state machine that does the I/O before or after executing the transition?
The I/O is done using the mutable reference to the UntypedStateMachine in the functions.
For example UntypedStateMachine could just be a vec that you append to or read from.
If you want to model cases with failure your return type will be
Result<StateMachine<Reserved>, Error>
A conditional transition should return something like
(StateMachine<PostConditional>, ConditionalData)
I think this makes sense. I’m eager to try it. Some residual questions: what is “untyped” in this case and what is “PostConditional” (an enum of possible states?)? How do subsequent transitions work?
I also just realized that delegating to “UntypedStateMachine” for I/O probably doesn’t allow for Sans-I/O, right? Presumably the UntypedStateMachine must commit to either being sync or async and that must propagate to the typestate state machine itself, no?